Error. Access token expired


I can not log in to my account using my application.

I’m get this message:
404: {“errors”:[{“message”:“Sorry, that page does not exist”,“code”:34}]}

and when i hit back this message appear:
“The request token for this page is invalid. It may have already been used, or expired because it is too old. Please go back to the site or application that sent you here and try again; it was probably just a mistake”

Please enlight me. I’m using Dabr